Working Principle of MOSFETs:
MOSFETs are comprised of three regions: the source, drain, and gate. The source and drain regions are heavily doped with an impurity to make them conductive, while the gate region is lightly doped to make it resistive. The gate is separated from the source and drain regions by a thin dielectric layer, typically made of silicon dioxide (SiO2).
When a positive voltage is applied to the gate, an electric field is created in the dielectric layer, which attracts the free electrons from the source and drain regions towards the gate. This forms a channel between the source and drain regions, allowing current to flow from the source to the drain. This state is referred to as the "On" state of the MOSFET.
In contrast, when the voltage at the gate is negative, the electric field in the dielectric layer repels the electrons from the gate, effectively closing the channel. This state is referred to as the "Off" state of the MOSFET.
Applications of MOSFETs:
MOSFETs are commonly used as electronic switches or amplifiers. As a switch, a MOSFET can control the flow of current between the source and drain regions by varying the voltage applied to the gate. As an amplifier, the MOSFET can amplify the input signal by controlling the current flow through the channel.
Conclusion:
MOSFETs are versatile and widely used electronic components due to their fast switching speed, low power consumption, and high input impedance. Understanding the working principle of MOSFETs is essential for their proper usage in electronic devices.
